Displaying 3 results from an estimated 3 matches for "ensurelocal".
2013 Jan 05
0
Small changes to big objects (2): Local Reference Classes
...the object will cause internal duplication of the whole
thing, in the very likely case that we pass some object, myX say as
argument x to a function.
As soon as the evaluator sees a replacement function, "@<-", "$<-" or
"attr<-" for an ordinary object, the EnsureLocal routine calls
duplicate() if the object has more than one reference, as it will in
this scenario. And BigData gets copied. I think it's important to
understand that this follows from the "replacement function" concept in
S and R: A replacement function takes an object from the f...
2013 Jan 03
3
Small changes to big objects (1)
...r in behavior with one important
exception--fixing that is the automatic change.
I need to review what R does here. All these are replacement functions,
`@<-`, `attr<-`, `$<-`. The evaluator checks before calling any
replacement whether the object needs to be duplicated (in a routine
EnsureLocal()). It does that by examining a special field that holds
the reference status of the object.
Some languages, such as Python (and S) keep reference counts for each
object, de-allocating the object when the reference count drops back to
zero. R uses a different strategy. Its NAMED() field is 0,...
2004 Sep 13
6
Spare some CPU cycles for testing lme?
If anyone has a few extra CPU cycles to spare,
I'd appreciate it if you could verify a problem that I
have encountered. Run the code
below and tell me if it crashes your R before
completion.
library(lme4)
data(bdf)
dump<-sapply( 1:50000, function(i) {
fm <- lme(langPOST ~ IQ.ver.cen + avg.IQ.ver.cen, data = bdf,
random = ~ IQ.ver.cen | schoolNR);
cat("